A cooling mechanism is essential to a data center in which a large number of IT machines (heat radiating machines) such as servers and network machines are installed, and the cooling mechanism serves to cool the IT machines such that the temperatures of the IT machines do not become equal to or higher than a predetermined temperature (about 27 to 30° C.), in order to stably operate the IT machines.
In the indoor space of such a data center, people stay for an extremely short time except during maintenance, and the amount of ventilation is small. Hence, the latent heat load is low. Meanwhile, the amount of heat radiated from the heat radiating machines is enormous. Hence, the sensible heat load is high, and the load exists over the entire indoor space.
Under the present circumstances, such a configuration that feeds cool air generated by a cooling apparatus into the heat radiating machines using an air blowing apparatus is the mainstream of the cooling mechanism (see, for example, Patent Literature 1).
However, the cooling mechanism according to such a method has the following and other problems: the power consumption of the air blowing apparatus is enormous due to a great amount of blown air and a long air blowing distance; a large space is necessary for the air blowing; and temperature unevenness occurs due to an attempt to uniformly cool a large space.
In addition to the above-mentioned method, there is a water cooling mechanism in which: a circulation route is formed so as to surround the heat radiating machines; and a cooling medium is circulated in the circulation route. However, in the case where liquid leakage occurs, the risk that the IT machines may be damaged cannot be completely eliminated. Hence, the water cooling mechanism cannot necessarily be considered to be suitable for the data center that is required to have stability and reliability.
As described above, under the present circumstances, in order to stably operate the data center, no cooling mechanism can sufficiently satisfy both of the following: prevention of dust penetration, water droplet occurrence, and water leakage; and a reduction in running costs such as consumed electric power.
Note that the following problem also exists. That is, if a fire breaks out in the data center due to electrical leakage or the like, water is discharged by a sprinkler or the like. Hence, not only machines near the origin of the fire but also other machines become inoperable, and a great amount of data is lost.